This invention relates generally to sealing washers and more particularly to sealing washers of a composite variety which are capable of spring loading a clamped joint.
Rubber-like sealing rings have heretobefore been associated with rigid washer devices in such a manner that the sealing washer is compressed beneath the rigid washer serving to prevent moisture from entering the joint. Such devices do not have the capability of providing a continual spring load to the bolt in the fastened joint. Other prior art devices of a sealing washer variety utilize a spring-type washer with a sealing material positioned beneath the washer and more particularly between the workpiece and the clamping surface of the washer. This type of device produces a bolt load loss due to the cold flow of the sealing material beneath the clamping surface of the washer. The load on the bolt resulting from the spring surface will decrease over a period of time.
Still further prior art sealing washers utilize a sealing ring or sealing material beneath the surface of a spring washer located interiorly of the outer clamping surface. This type of configuration does not permit the minimization of the material thickness of the spring washer for a given load desired since the clamp load diameter of the washer must always be greater than the sealing ring diameter.